In recent years, there has been progress in the development of light-emitting devices using organic EL. Such light-emitting devices are used as illumination devices or display devices and configured of an organic layer interposed between a first electrode and a second electrode. Generally, a transparent material is used for the first electrode, and a metal material is used for the second electrode.
One of the light-emitting devices which utilizes the organic EL is a technology described in Patent Document 1. In order to provide an organic EL element with optical transparency (or a “see-through” property), the second electrode is provided only in a portion of a substrate in the technology in Patent Document 1. In such a structure, since a region located between a plurality of second electrodes transmits light, the organic EL element is capable of having optical transparency. In Patent Document 1, a sealing structure of an organic EL element is a hollow sealing structure.
Further, Patent Document 2 describes sealing the organic EL element by covering the organic EL element with a sealing film and using a sealing plate in an organic EL display device having optical transparency.